Move Thread Name Mapping into ThreadFunc.

base/threading/platform_thread_win.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/threading/platform_thread.h"
 
 #include "base/debug/alias.h"
 #include "base/debug/profiler.h"
 #include "base/logging.h"
 #include "base/threading/thread_id_name_manager.h"
@@ skipping 28 matching lines @@
   __try {
     RaiseException(kVCThreadNameException, 0, sizeof(info)/sizeof(DWORD),
                    reinterpret_cast<DWORD_PTR*>(&info));
   } __except(EXCEPTION_CONTINUE_EXECUTION) {
   }
 }
 
 struct ThreadParams {
   PlatformThread::Delegate* delegate;
   bool joinable;
+  PlatformThreadHandle* thread_handle;
 };
 
 DWORD __stdcall ThreadFunc(void* params) {
   ThreadParams* thread_params = static_cast<ThreadParams*>(params);
   PlatformThread::Delegate* delegate = thread_params->delegate;
   if (!thread_params->joinable)
     base::ThreadRestrictions::SetSingletonAllowed(false);
+
+  ThreadIdNameManager::GetInstance()->RegisterThread(
+      thread_params->thread_handle,
+      PlatformThread::CurrentId());
   delete thread_params;
   delegate->ThreadMain();
   return NULL;

[jar (doing other things), 2013/05/22 19:37:56]

Wouldn't this be a great place to unregister, just in front of line 63?  ...
while the thread is still active... but about to terminate.... so it would be a
bad thing for folks to refer to us anyway IMO.

[Same thing in platform_thread_posix.cc]

[dsinclair, 2013/05/22 20:22:31]

The benefit I see from having it in the Join method of PlatformThread is that we
know all posted tasks are done. My concern was that, things like
MessageLoop::PostTask, use the thread name when they do TRACE_EVENT calls.

[jar (doing other things), 2013/05/22 21:36:48]

I think that by the time you hit line 63, any message loop on this thread should
be gone... so the question is: Who can/should be referencing the thread, and
asking questions about it?  Surely we won't be askin' any more questions
(tracing any more calls), as we're exiting here.

[dsinclair, 2013/05/23 18:21:53]

Done.

 }
 
 // CreateThreadInternal() matches PlatformThread::Create(), except that
 // |out_thread_handle| may be NULL, in which case a non-joinable thread is
 // created.
 bool CreateThreadInternal(size_t stack_size,
                           PlatformThread::Delegate* delegate,
                           PlatformThreadHandle* out_thread_handle) {
   PlatformThreadHandle thread_handle;
   unsigned int flags = 0;
   if (stack_size > 0 && base::win::GetVersion() >= base::win::VERSION_XP) {
     flags = STACK_SIZE_PARAM_IS_A_RESERVATION;
   } else {
     stack_size = 0;
   }
 
   ThreadParams* params = new ThreadParams;
   params->delegate = delegate;
   params->joinable = out_thread_handle != NULL;
+  params->thread_handle = out_thread_handle;
 
   // Using CreateThread here vs _beginthreadex makes thread creation a bit
   // faster and doesn't require the loader lock to be available.  Our code will
   // have to work running on CreateThread() threads anyway, since we run code
   // on the Windows thread pool, etc.  For some background on the difference:
   //   http://www.microsoft.com/msj/1099/win32/win321099.aspx
   thread_handle = CreateThread(
       NULL, stack_size, ThreadFunc, params, flags, NULL);
   if (!thread_handle) {
     delete params;
@@ skipping 108 matching lines @@
     case kThreadPriority_Normal:
       ::SetThreadPriority(handle, THREAD_PRIORITY_NORMAL);
       break;
     case kThreadPriority_RealtimeAudio:
       ::SetThreadPriority(handle, THREAD_PRIORITY_TIME_CRITICAL);
       break;
   }
 }
 
 }  // namespace base